http://www.ck12.org Chapter 5. Forces in Two Dimensions
An Incline Plane-Pulley System
Illustrative Example
How do we determine the acceleration and the tension between two masses when one of the masses is on the inclined
plane and the other hangs over the plane, as inFigure5.15?
FIGURE 5.15
Again, we call on Newton’s Second Law in order to solve the system. Let’s assume there is no friction in the system
and the rope between the masses does not stretch and has negligible mass. The values for the masses and the angle
of the incline are given below.
M= 40. 0 kg
m= 30. 0 kg
θ= 25. 0 ◦
Find, (A) the acceleration of the system and (B) the tension in the rope.
Finding the acceleration of the systemWe always start by drawing FBDs and resolving vectors.
- Draw an FBD for each mass.
FIGURE 5.16
- Resolve any vectors that are not along thexoryaxes.
Thex−component ofMg:Mgsinθ